This blog continues the discussion that we began with Epic Journey: The 2008 Elections and American Politics (Rowman and Littlefield, 2009).The latest book in this series is Defying the Odds: the 2016 Elections and American Politics.

Twenty years ago, half the 12 largest U.S. municipalities had a Republican mayor. When Bill de Blasio takes office in New York on Jan. 1, none will.

As middle-class residents moved out of cities and immigrants and young people replaced them, the party lost its grip on population centers even as it increased control of governor’s offices and legislatures. The polarization has pitted urban interests against rural areas and suburbs, denying Republicans a power base.

“The New York election hopefully is somewhat of a wake-up call,” said Scott Smith, the Republican mayor of Mesa, Arizona, and president of the U.S. Conference of Mayors. “If that doesn’t get Republicans on the national level more interested, then it should.”

De Blasio’s election means that besides New York, there will be Democratic mayors next year in Los Angeles; Chicago; Houston; Philadelphia; Phoenix; San Antonio; Dallas; San Jose, California; Austin, Texas; and Jacksonville, Florida. A runoff will be held in February in San Diego to replace Democratic Mayor Bob Filner, who resigned in August amid charges of sexual harassment.

In New York, Democrats outnumber Republicans more than 6-to-1, yet voters hadn’t elected a Democrat since David Dinkins lost to Rudolph Giuliani in 1993. De Blasio, 52, won this month by the biggest margin by a non-incumbent in city history on vow to close the growing gap between rich and poor.